ASC-H cytological result: clinical relevance and accuracy of colposcopy in predicting high-grade histological lesions—a 7-year experience of a single institution in Portugal

Atypical squamous cells, cannot exclude high-grade squamous intraepithelial lesion (ASC-H) represents an interpretative challenge in clinical practice. We aimed to evaluate the histological outcome of ASC-H cytology and to evaluate the accuracy of colposcopy in predicting high-grade histological lesions. Retrospective study of ASC-H cervical cytology results, from January 2010 to December 2016, at a tertiary hospital. Demographic characteristics, colposcopic findings, diagnostic procedures, and histological outcomes were analyzed using SPSS, version 22.0. ASC-H prevalence was 0.25%. Patient mean age was 42.02 ± 12.8 years. The overall incidence of cervical dysplasia of any grade was 83.6% (n = 56) and the incidence of high-grade lesions was 50.8% (n = 34) (including 1 case of in situ adenocarcinoma and 2 cases of squamous cell carcinoma). Among patients with type 1 or 2 transformation zone (TZ), 84.9% (n = 45) had abnormal colposcopic findings, with 62.2% (n = 28) corresponding to grade 2 and 37.8% (n = 17) to grade 1. Colpo-histologic concordance was 85.4% (82.1% for grade 2 lesions and 100% for grade 1 lesions). The sensitivity, specificity, positive predicted value (PPV) and negative predictive value (NPV) was 100%, 75%, 82.1%, and 100%, respectively. The histological study of patients with type 3 TZ revealed 45.8% (n = 11) of high-grade lesions. ASC-H is strongly associated with high-grade histological lesions. Immediate evaluation of patients with this cytology abnormality is therefore mandatory. Colposcopy, when performed by expert clinicians, has great accuracy in detecting high-grade lesions. Histological evaluation of patients with type 3 TZ is extremely important because almost 50% of patients have this type of lesion.